Technology enabling the customer to acquire information printed on a receipt in POS systems that execute sale processes, for example, is known from the literature (see, for example, PTL 1). In the system disclosed in PTL 1, a server computer stores a database of receipt information and an e-mail database storing e-mail addresses used to retrieve the receipt information; and when a POS register installed in a store runs a sale process and prints a receipt, the server computer issues a receipt ID, and generates and sends an e-mail address containing this receipt ID to the POS register. The POS register then prints purchase history information with the e-mail address on the receipt, and the customer can acquire this information using this e-mail address.